Growth and characterization of high-quality and large-scale piperazinium bis (trifluoroacetate) single crystal using the immersing ampoule Sankaranarayanan-Ramasamy (ISR) method for nonlinear optical applications

The optically good quality organic piperazinium bis(trifluoroacetate) (80 mm in length and 15 mm in diameter) single crystal was grown by Immersing Ampoule Sankaranarayanan-Ramasamy (ISR) method at ambient temperature using water as solvent. The ampoule was specially designed for the growth of good quality and bulk size unidirectional single crystal by slow cooling condition. The unwanted temperature gradient developed on the solution surface was completely avoided, hence the formation of secondary nucleation on top of the ampoule is avoided. The growth apparatus and optimization parameters have been made simpler compared to the conventional SR method. Growth direction parallel to the gravity direction can be easily achieved, hence slanted growth could be avoided within the ampoule and also linear transportation of embryos from solution to crystal-solution interface is achieved. The ISR method-grown single crystal was subjected to various characterizations. The grown PTFA crystal was subjected to Single crystal X-ray diffraction (SXRD), Powder X-ray diffraction, UV-Visible-NIR, Fourier Transform Infrared (FTIR) analysis, Chemical etching analysis, Birefringence, and Z-scan analysis. The structural properties revealed that the PTFA crystal belongs to a triclinic crystal system with a space group P-1. Using powder XRD analysis, miller index and (h k l) planes were identified. The FTIR analysis was investigated on the PTFA crystal to find out the PTFA functional groups. The chemical etching was investigated to calculate the etch pit density. The optical homogeneity of ISR method-grown crystals was measured by the Birefringence method. The third-order nonlinear optical (NLO) properties of the grown crystal, such as absorption coefficient, refractive index, and susceptibility range values estimated by the Z-scan technique suggest that the grown crystal material PTFA can serve as a promising candidate for nonlinear optical devices. The novel crystal growth ISR method has been reported, and also various studies reveal that the ISR method-grown crystals are favorable for high-performance optical device applications.